Transporting products via unmanned aerial vehicles (UAVs) over populated areas such as towns and cities requires UAV operators to consider the risks associated with unexpected malfunctions, in-air collisions, and/or other emergency events that may lead to emergency crash landings of the UAVs. Given that the UAVs, both when empty and when carrying cargo, can present a significant injury risk to people and animals on the ground as well as a personal property risk to buildings and cars on the ground in the event that the UAVs crash land, especially in a densely populated area such as a city, early warnings of such potential crash landings is desirable.
Elements in the figures are illustrated for simplicity and clarity and have not been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. Certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.